2004 - what tire sizes in CPM

[DieselDoghouse]

Guys this is not fur me - I'm 12V second gen. But I hope to bring a neighbor and decent guy into the fold. Has a recently acquired 2004 bought in the midwest with 35 inch tires. Speedo apparently not corrected. What tire sizes are "native" in the CPM and could be selected with a scan tool?? Otherwise I would guess he would need a Tru-speed or equiv. as I did. Any help appreciated. I will relay until he is enrolled…Oh, there are several Ferds in his family:-laf

 

[cerberusiam]

On that year of truck you can set the pinion ratio or whatever they call it. Mark the tire and rotate on the ground once to measure the distance traveled in 1 rev. That will allow you to punch the number into the OEM reader. It might have 35" tires in there but not sure.



Or buy a Smarty and set it by tire height.

 

[Kry226]

Correct. In my truck, the dealer simply set the revolutions per mile, as listed for the BFG 315s in BFG's tech data. Most tire MFRs will list this data for each tire.